Aquaculture Studies 2017, Vol 17, Num, 4     (Pages: 349 - 360)

A Study of the Behavior of Harbour Crab (Liocarcinus depurator) in Beam Trawl Used in the Rapa Whelk Fishery in Black Sea

Ahmet Raif ERYAŞAR

1 Recep Tayyip Erdoğan Universitesi, Teknik Bilimler Meslek Yüksekokulu, Su Altı Teknolojisi Programı, Rize, Türkiye DOI : 10.17693/yunusae.v17i31121.332657 Viewed : 136 - Downloaded : 50 Behavior observations of harbour crab (Liocarcinus depurator) in the effect area of beam trawls used for rapa whelk (Rapana venosa) fisheries in the Eastern Black Sea were made with a charetered commercial vessel between 17 - 19 December 2015. Hauls were made in natural light conditions at depths of 16 - 18 meters and a total of 403 minutes of usable image was obtained. Observations made in the mounth of the beam trawl showed that 89% of shore crabs were actively escaping from the beam trawl. To escape from the approaching the beam trawl, individuals showed walking and raising behaviour. Observations made in the codend showed that 87% of shore crab individuals are positioned above the sand cloud. Finally, proposals about elimination of this species from the beam trawl are submitted using findings obtained from this study. Keywords : Eastern Black Sea, rapa whelk, beam trawl, shore crab, behavior